Arsenal manager Arsene Wenger has admitted that he doubted whether Alexis Sanchez could play as a main striker in the Premier League.

The Chilean has established himself as Arsenal's leading marksman so far this season, with his hat-trick during last weekend's 5-1 victory over West Ham United taking his tally to a joint league-high 11 goals.

Before this season, Sanchez had spent most of his Arsenal career in a wider role, but Wenger is happy with how he has adapted to playing through the middle after some less successful auditions in previous years.

"I must honestly say I thought many times when I played him last year or two years ago I was wrong. The few experiences I attempted with him through the middle were not convincing and I remember even in one game I changed it at half time. This year it clicked very early in the season," he told reporters.

"He has developed very well as a centre forward because I think he has found a good mixture between being coming off and going in behind and he has more freedom as well and he takes advantage of his short technique in the middle much more. I had to persuade Thierry [Henry to move centrally]. I don't know if it's my greatest achievement. You see the guy who plays wide can score goals that he can in the centre score even more goals.

"At the start of the season when he came back and he took advantage of the fact [Olivier] Giroud was not here and not ready so I could give him more games. Sometimes when you have too many people you cannot lost long an experience that is not immediately conclusive because you are under pressure. It doesn't work one or two games and you have a top player on the bench you're tempted very early to change it."

Sanchez is already just two goals short of his Premier League tally for the whole of last season.